Cement compositions comprising particulate foamed elastomers and associated methods

ABSTRACT

Methods of subterranean cementing involving cement compositions comprising particulate foamed elastomers and associated methods are provided. In one embodiment, the methods comprise introducing a cement composition into a subterranean location, wherein the cement composition comprises a hydraulic cement, a particulate foamed elastomer, and an aqueous fluid; and allowing the cement composition to set in the subterranean location.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending U.S. patent applicationSer. No. 12/484,715, filed Jun. 15, 2009, which is herein incorporatedby reference.

BACKGROUND

The present invention relates to cementing operations and, moreparticularly, in certain embodiments, to cement compositions comprisingparticulate foamed elastomers and associated methods.

Cement compositions may be used in a variety of subterraneanapplications. For example, in subterranean well construction, a pipestring (e.g., casing, liners, expandable tubulars, etc.) may be run intoa well bore and cemented in place. The process of cementing the pipestring in place is commonly referred to as “primary cementing.” In atypical primary cementing method, a cement composition may be pumpedinto an annulus between the walls of the well bore and the exteriorsurface of the pipe string disposed therein. The cement composition mayset in the annular space, thereby forming an annular sheath of hardened,substantially impermeable cement (i.e., a cement sheath) that maysupport and position the pipe string in the well bore and may bond theexterior surface of the pipe string to the subterranean formation. Amongother things, the cement sheath surrounding the pipe string functions toprevent the migration of fluids in the annulus, as well as protectingthe pipe string from corrosion. Cement compositions also may be used inremedial cementing methods, for example, to seal cracks or holes in pipestrings or cement sheaths, to seal highly permeable formation zones orfractures, to place a cement plug, and the like.

Set cement in wells, and particularly the set cement sheath in theannulus of a well, may fail due to, inter alia, shear, tensile andcompressional stresses exerted on the set cement. There are severalstressful conditions that have been associated with well bore cementfailures. One example of such a condition results from the relativelyhigh fluid pressures and/or temperatures inside of the set casing duringtesting, perforation, fluid injection, or fluid production. If thepressure and/or temperature inside the pipe increases, the resultantinternal pressure may expand the pipe, both radially and longitudinally.This expansion generally may place stress on the cement surrounding thecasing causing it to crack, or the bond between the outside surface ofthe pipe and the cement sheath to fail in the form of, inter alia, lossof hydraulic seal. Another example of such a stressful condition iswhere the fluids trapped in a cement sheath thermally expand potentiallycausing high pressures within the sheath itself. This condition oftenoccurs as a result of high temperature differentials created duringproduction or injection of high temperature fluids through the wellbore, e.g., wells subjected to steam recovery processes or theproduction of hot formation fluids. Other stressful conditions that canlead to cement failures include the forces exerted by shifts in thesubterranean formations surrounding the well bore or other over-burdenedpressures.

Failure of cement within the well bore can result in cracking of thecement as well as a breakdown of the bonds between the cement and thepipe or between the cement sheath and the surrounding subterraneanformations. Such failures can result in at least lost production,environmental pollution, hazardous rig operations, and/or hazardousproduction operations. A common result is the undesirable presence ofpressure at the well head in the form of trapped gas between casingstrings. Additionally, cement failures can be particularly problematicin multi-lateral wells, which include vertical or deviated (includinghorizontal) principal well bores having one or more ancillary, laterallyextending well bores connected thereto.

Elastomeric materials, such as rubber particles, have previously beenincluded in cement compositions to modify the mechanical properties ofthe set cement, including Young's Modulus, Poisson's Ration, and thecompressive and tensile strength. However, these elastomeric materialsmay segregate during the placing and setting of the cement, leading toan undesirable density gradient in the set cement.

SUMMARY

The present invention relates to cementing operations and, moreparticularly, in certain embodiments, to cement compositions comprisingparticulate foamed elastomers and associated methods.

An embodiment of the present invention provides a method comprisingintroducing a cement composition into a subterranean location, whereinthe cement composition comprises a hydraulic cement, a particulatefoamed elastomer, and an aqueous fluid; and allowing the cementcomposition to set in the subterranean location.

Another embodiment of the present invention provides a method comprisingintroducing a cement composition into a space between a pipe string anda subterranean formation, wherein the cement composition comprises ahydraulic cement, a particulate foamed elastomer, and an aqueous fluid;and allowing the cement composition to set in the space.

In yet another embodiment, the present invention provides a cementcomposition comprising: a hydraulic cement, a particulate foamedelastomer, and an aqueous fluid.

The features and advantages of the present invention will be readilyapparent to those skilled in the art. While numerous changes may be madeby those skilled in the art, such changes are within the spirit of theinvention.

DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention relates to cementing operations and, moreparticularly, in certain embodiments, to cement compositions comprisingparticulate foamed elastomers and associated methods.

There may be several potential advantages to the methods andcompositions of the present invention, only some of which may be alludedto herein. One of the many potential advantages of the methods andcompositions of the present invention is that the mechanical propertiesof the cement composition may be adjusted so that the cement compositionhas more desirable properties for a particular purpose. Anotherpotential advantage of the methods and compositions of the presentinvention is that the use of particulate foamed elastomers may solveproblems associated with segregation of the elastomers during thesetting of the cement composition. In some embodiments, anotherpotential advantage is that particulate foamed elastomers included inthe cement compositions of the present invention may swell whencontacted by gas, hydrocarbons, and/or water thus providing“self-healing” properties in the event the cement sheath is damaged orcracked. The increased surface area of the particulate foamed elastomermay facilitate a quicker response to a fluid infiltrating a crackedcement matrix such that the particulate foamed elastomer may swell tofill the crack in a timely manner.

In certain embodiments, cement compositions of the present inventiongenerally comprise a cement, a particulate foamed elastomer, and anaqueous fluid. Those of ordinary skill in the art will appreciate thatthe cement compositions generally should have a density suitable for aparticular application. By way of example, cement compositions of thepresent invention may have a density of from about 4 pounds per gallon(“lb/gal”) to about 20 lb/gal. In certain embodiments, the cementcompositions may have a density of from about 8 lb/gal to about 17lb/gal. Cement compositions of the present invention may be foamed orunfoamed or may comprise other means to reduce their densities, such ashollow microspheres, low-density elastic beads, or otherdensity-reducing additives known in the art. Those of ordinary skill inthe art, with the benefit of this disclosure, will recognize theappropriate density for a particular application.

As described above, the cement compositions of the present inventioncomprise a cement. Any of a variety of cements suitable for use insubterranean cementing operations may be used in accordance withembodiments of the present invention. Suitable non-limiting examplesinclude hydraulic cements that comprise calcium, aluminum, silicon,oxygen and/or sulfur, which set and harden by reaction with water. Suchhydraulic cements, include, but are not limited to, Portland cements,pozzolana cements, gypsum cements, high-alumina-content cements, slagcements, silica cements, cement kiln dust (“CKD”), and combinationsthereof. “CKD,” as that term is used herein, refers to a partiallycalcined kiln feed which may be removed from the gas stream andcollected in a dust collector during the manufacture of cement. CKDgenerally may comprise a variety of oxides, such as SiO₂, Al₂O₃, Fe₂O₃,CaO, MgO, SO₃, Na₂O, and K₂O. In certain embodiments, the hydrauliccement may comprise a Portland cement. The Portland cements that may besuited for use in embodiments of the present invention are classified asClass A, C, H and G cements according to American Petroleum Institute,API Specification for Materials and Testing for Well Cements, APISpecification 10A, 23rd Ed., Apr. 1, 2002.

In some embodiments, the cement compositions of the present inventioncomprise a particulate foamed elastomer. In general, particulate foamedelastomers suitable for use in the present invention may have an opencell structure that is permeable to both the dry and wet constituents ofthe cement slurry. It is believed that this structure may facilitate themixing and dispersion of the cement slurry and the adhesion of theparticles to the set cement. Therefore, suitable particulate foamedelastomers should be foamed prior to being placed into the cementcomposition. As mentioned above, one advantage of using particulatefoamed elastomers, as compared to unfoamed elastomers, is that theparticulate foamed elastomers may stay more evenly dispersed throughoutthe cement composition, rather than segregating, as the cementcomposition sets. In certain embodiments, a particulate foamed elastomersuitable for use in the cement compositions of the present invention maycomprise a polyurethane foam. Examples of suitable polyurethane foam aredescribed in U.S. Pat. No. 4,892,891 issued to Close, the entiredisclosure of which is herein incorporated by reference. While manysuitable foamed elastomers are commercially available, in oneembodiment, a suitable foamed elastomer may be produced by blowing airinto a suitable elastomer while it is in a molten state or using anin-situ material that would evolve a gas and subsequently foam theelastomer.

In some embodiments, a particulate foamed elastomer suitable for use inthe present invention may be a foamed swellable elastomer. As usedherein, an elastomer is characterized as swellable when it swells uponcontact with gas, hydrocarbons, or water. Foamed swellable elastomerssuitable for use in some embodiments of the present invention maygenerally swell by up to about 50% of their original size at thesurface. Under downhole conditions, this swelling may be more, or less,depending on the conditions presented. For example, the swelling may beat least 10% at downhole conditions. In some embodiments, the swellingmay be up to about 50% under downhole conditions. However, as those ofordinary skill in the art, with the benefit of this disclosure, willappreciate, the actual swelling when the foamed swellable elastomer isincluded in a cement composition may depend on, for example, theconcentration of the foamed swellable particle included in the cementcomposition, downhole pressure, and downhole temperature, among otherfactors.

Examples of suitable foamed swellable elastomers that may swell when incontact with a hydrocarbon or gas include, but are not limited to,foamed versions of the following: EPDM (ethylene propylene diene M-classrubber), polyamide, polypropylene, polyethylene, styrene butadiene,styrene, divinylbenzene, natural rubber, acrylate butadiene rubber,polyacrylate rubber, isoprene rubber, choloroprene rubber, butyl rubber(IIR), brominated butyl rubber (BIIR), chlorinated butyl rubber (CIIR),chlorinated polyethylene (CM/CPE), neoprene rubber (CR), styrenebutadiene copolymer rubber (SBR), sulphonated polyethylene (CSM),ethylene acrylate rubber (EAM/AEM), epichlorohydrin ethylene oxidecopolymer (CO, ECO), ethylene-propylene rubber (EPM and EDPM),ethylene-propylene-diene terpolymer rubber (EPT), ethylene vinyl acetatecopolymer, fluorosilicone rubbers (FVMQ), silicone rubbers (VMQ), poly2,2,1-bicyclo heptene (polynorborneane), alkylstyrene, nitrile rubber(NBR), hydrogenated nitrile rubber (HNBR, HNS), fluoro rubbers (FKM),perfluoro rubbers (FFKM), tetrafluorethylene/propylene (TFE/P), anyderivative thereof, and any combination thereof. Examples of suitablefoamed swellable elastomers that may swell when in contact with waterinclude, but are not limited to, foamed versions of the following:isobutylene maleic anhydride, starch-polyacrylate acid graft copolymerand salts thereof, polyethylene oxide polymer, carboxymethyl cellulosetype polymers, polyacrylamide, poly(acrylic acid) and salts thereof,poly(acrylic acid-co-acrylamide) and salts thereof, graft-poly(ethyleneoxide) of poly(acrylic acid) and salts thereof, poly(2-hydroxyethylmethacrylate), and poly(2-hydroxypropyl methacrylate), any derivativethereof and any combination thereof. Combinations of the foamedelastomers may include blends and mixtures as well as copolymers andterpolymers.

In certain embodiments, a foamed swellable elastomer may be encapsulatedwith a slowly water-soluble or other suitable encapsulating material soas to delay the swelling of the elastomer. Such materials are well knownto those skilled in the art and function to delay the swelling of thefoamed swellable elastomer for a required period of time. Examples ofwater-soluble and other similar encapsulating materials that may besuitable include, but are not limited to, porous solid materials such asprecipitated silica, elastomers, polyvinylidene chloride (PVDC), nylon,waxes, polyurethanes, polyesters, cross-linked partially hydrolyzedacrylics, other polymeric materials, and the like.

The foamed particulate elastomer may be present in the cementcompositions in an amount sufficient to provide the desired mechanicalproperties. In certain embodiments, the particulate foamed elastomer maybe present in the cement compositions in an amount of from about 0.5% toabout 50% by weight of the cement on a dry basis (“bwoc”). In otherembodiments, the particulate foamed elastomer may be present in thecement compositions of from about 0.5% to about 30% by weight of thecement on a dry basis. In other embodiments, the particulate foamedelastomer may be present in the cement compositions of from about 2% toabout 10% by weight of the cement on a dry basis. In some embodiments,suitable foamed particulate elastomers may be prepared by grinding afoamed elastomer into a dry powder. This preparation method does notdestroy the open cell structure. Any other suitable means of producing aparticulate form of the foamed elastomer may also be used. In certainembodiments, the foamed particulate elastomer comprises particles thatgenerally range in size from about 40 to about 1000 microns. In oneembodiment, the foamed particulate elastomers comprise particles belowabout 600 microns but above about 60 microns in size. As used herein,particle size generally refers to the length of the largest dimension ofthe particle. The open cell structure of the individual particles,however, includes features that are smaller in size.

As described above, the cement compositions of the present invention maycomprise an aqueous fluid. Examples of suitable aqueous fluids mayinclude fresh water, salt water, brine (e.g., saturated saltwater), orseawater. Generally, the water may be from any source, provided that itshould not contain an excess of compounds that may undesirably affectother components in the cement composition. Further, the aqueous fluidmay be present in an amount sufficient to form a pumpable slurry. Incertain embodiments, the aqueous fluid may be present in the cementcomposition in an amount of from about 33% to about 200% bwoc. In otherembodiments, the aqueous fluid may be present in the cement compositionof from about 35% to about 70% bwoc. One of ordinary skill in the artwith the benefit of this disclosure will recognize the appropriateamount of aqueous fluid for a chosen application.

Additives suitable for use in subterranean cementing operations also maybe included in the cement compositions of the present invention.Examples of such additives may include, but are not limited to,strength-retrogression additives, set accelerators, set retarders,weighting agents, weight-reducing additives, heavyweight additives,lost-circulation materials, filtration-control additives, dispersants,defoaming agents, foaming agents, and combinations thereof. Specificexamples of these, and other, additives include crystalline silica,amorphous silica, salts, fibers (including, but not limited to, glass,carbon, and metal fibers), hydratable clays, vitrified shale,microspheres, fly ash, lime, latex, thixotropic additives, combinationsthereof and the like. A person having ordinary skill in the art, withthe benefit of this disclosure, will readily be able to determine thetype and amount of additive useful for a particular application anddesired result.

As will be appreciated by those of ordinary skill in the art, the cementcompositions of the present invention may be used in a variety ofsubterranean applications, including primary and remedial cementing. Forexample, the cement compositions may be introduced into a subterraneanformation and allowed to set. By way of example, in primary cementingembodiments, a cement composition may be introduced into a space betweena subterranean formation and a pipe string located in the subterraneanformation. The cement composition may be allowed to set to form ahardened mass in the space between the subterranean formation and thepipe string. In addition, in example remedial cementing embodiments, acement composition of the present invention may be used, for example, insqueeze cementing operations or in the placement of cement plugs. Insome embodiments, a cement composition of the present invention may beplaced in or near a crack in a cement matrix so that a foamedparticulate elastomer may swell to fill the crack.

To facilitate a better understanding of the present invention, thefollowing examples of certain aspects of some embodiments are given. Inno way should the following examples be read to limit, or define, theentire scope of the invention.

EXAMPLE 1

A 16.4 lb/gal Portland class H cement slurry was prepared. Apolyurethane foam ground below 80 microns in particle size was added tothe slurry. For comparison purposes, several samples were prepared withthe polyurethane foam present in concentrations of 1% and 5% by weightof cement. After preparation, the slurries were cured at 140° F. for 7days. The samples were prepped for mechanical property evaluationfollowing ASTM D 4543. The Young's modulus, Poisson's ratio, andcompressive strength were tested following ASTM D 3148-02. The tensilestrength was measured following ASTM D 3967. Physical and mechanicalproperties are reported in Table 1 and Table 2.

TABLE 1 Polyurethane, by Compressive weight of cement Strength (psi)Young's Modulus Poisson's Ratio 1% 6,148 1.88E+06 0.179 1% 6,9071.98E+06 0.210 1% 6,822 1.95E+06 0.222 5% 5,490 1.46E+06 0.217 5% 5,3031.46E+06 0.197 5% 5,690 1.43E+06 0.203

TABLE 2 Polyurethane, by weight Tensile Strength Average BrazilianTensile of cement (psi) Strength (psi) 1% 594 573 1% 551 1% 517 1% 6325% 580 565 5% 601 5% 571 5% 509

As illustrated in Tables 1 and 2, the use of particulate polyurethanefoam may provide a set cement with desirable properties.

EXAMPLE 2

To further evaluate the use of particulate polyurethane foam, another16.4 lb/gal Portland class H cement slurry was prepared. A particulatepolyurethane foam was added to the slurry. For comparison purposes,several samples were prepared with the polyurethane foam present inconcentrations of 5% and 10% by weight of cement. After preparation, theslurries were cured at 3000 psi and 140° F. for 7 days. The samples wereprepped for mechanical property evaluation following ASTM D 4543. TheYoung's modulus, Poisson's ratio, and compressive strength were testedfollowing ASTM D 3148-02. The tensile strength was measured followingASTM D 3967. Physical and mechanical properties are reported in Table 3and Table 4.

TABLE 3 Polyurethane, by Compressive weight of cement Strength (psi)Young's Modulus Poisson's Ratio 5% 2,288 1.07E+06 0.143 5% 2,1621.08E+06 0.141 5% 2,223 1.14E+06 0.159 10% 1,610 8.36E+05 0.156 10%1,402 7.53E+05 0.128 10% 1,585 8.76E+05 0.110

TABLE 4 Polyurethane, by weight Tensile Strength Average BrazilianTensile of cement (psi) Strength (psi) 5% 192 228 5% 262 5% 229 5% 23010% 187 185 10% 161 10% 189 10% 205

As illustrated in Tables 3 and 4, the use of particulate polyurethanefoam may provide a set cement with desirable properties.

EXAMPLE 3

To evaluate the physical and mechanical properties of cementcompositions comprising particulate polyurethane foam, as compared tocement compositions comprising unfoamed elastomers, several cementcompositions comprising either particulate polyurethane foam or unfoamedelastomers of a styrene-butadiene rubber (“SBR”) block copolymer wereprepared. Several 16.4 lb/gal Portland class H cement slurries wereprepared. Particulate polyurethane foam or unfoamed SBR elastomers wereadded to the cement slurries as indicated in the tables below. Theelastomers were present in both types of cement compositions in anamount of 5% by weight of cement. After preparation, the slurries werecured at 3000 psi and 140° F. for 7 days. The confining pressure of thesamples was 0 psi.

The samples were prepped for mechanical property evaluation followingASTM D 4543. The Young's modulus and Poisson's ratio were testedfollowing ASTM D 3148-02. The unconfined compressive strength wasmeasured following ASTM D 2664-95a. Physical and mechanical propertiesfor cement compositions comprising particulate polyurethane foam arereported in Table 5. Physical and mechanical properties for cementcompositions comprising unfoamed elastomers are reported in Table 6.

TABLE 5 Polyurethane, by Compressive weight of cement Strength (psi)Young's Modulus Poisson's Ratio 5% 2,288 1.07E+06 0.143 5% 2,1621.08E+06 0.141 5% 2,223 1.14E+06 0.159 10% 1,610 8.36E+05 0.156 10%1,402 7.53E+05 0.128 10% 1,585 8.76E+05 0.110

TABLE 6 SBR, by weight of Compressive cement Strength (psi) Young'sModulus Poisson's Ratio 5% 7,190 1.85E+06 0.169 5% 7,554 1.92E+06 0.1745% 7,614 1.94E+06 0.191 10% 4,834 1.36E+06 0.177 10% 5,417 1.61E+060.215 10% 5,334 1.59E+06 0.213

As illustrated in Tables 5 and 6, the use of particulate polyurethanefoam may provide a set cement with desirable properties.

EXAMPLE 4

Swelling tests were conducted on two 1 cm×1 cm square samples of foamedEPDM rubber. One sample was placed in water as a control while the othersample was placed in ESCAID™ 110 hydrocarbon commercially available fromExxon Mobil. Physical properties of each sample are reported in Table 5.

The same swelling test was performed on a cement composition comprisingfoamed EPDM rubber in an amount of 10% by weight of cement. Theelastomer swelled approximately 20% in size.

TABLE 7 Time (min) Sample in Water Sample in Oil  0 — —  5 min. Nochange 10% expansion 10 min. No change 20% expansion 25 min. No change20% expansion 45 min. No change 20% expansion 24 hours No change 20%expansion

As illustrated in Table 7, the use of a foamed swellable elastomer mayprovide a cement composition with desirable properties.

EXAMPLE 5

To evaluate the segregation properties of cement compositions comprisingparticulate polyurethane foam, as compared to cement compositionscomprising unfoamed elastomers, two cement compositions comprisingeither particulate polyurethane foam or unfoamed elastomers of astyrene-butadiene rubber (“SBR”) block copolymer were prepared. Two 16.0lb/gal Portland class H cement slurries were prepared. Particulatepolyurethane foam with an average size of about 3000 microns or unfoamedSBR elastomers were added to the cement slurries in an amount of 10% byweight of cement. In addition, the cement slurries comprised adispersant in an amount of 1% by weight of cement. After curing, thecement samples were cut into 3 segments in order to determine thedensity of the sample at the top, middle and bottom of the sample.Density variation from top to bottom is an indication of slurrysegregation that may be caused by heavy particles tending to settle tothe bottom and light particles tending to migrate toward the top.Density measurements were made using Archimedes principle. Thesegregation characteristics for the cement compositions after 24 hoursare reported in Table 8.

TABLE 8 Density of slurry segment containing Density of slurry segmentparticulate unfoamed containing particulate elastomer (ppg) polyurethanefoam (ppg) Top 15.86 15.88 Middle 15.93 15.86 Bottom 16.37 15.99

As illustrated in Table 8, the use of a foamed swellable elastomer mayprovide a cement composition with more desirable settling properties.

Therefore, the present invention is well adapted to attain the ends andadvantages mentioned as well as those that are inherent therein. Theparticular embodiments disclosed above are illustrative only, as thepresent invention may be modified and practiced in different butequivalent manners apparent to those skilled in the art having thebenefit of the teachings herein. Furthermore, no limitations areintended to the details of construction or design herein shown, otherthan as described in the claims below. It is therefore evident that theparticular illustrative embodiments disclosed above may be altered ormodified and all such variations are considered within the scope andspirit of the present invention. While compositions and methods aredescribed in terms of “comprising,” “containing,” or “including” variouscomponents or steps, the compositions and methods can also “consistessentially of” or “consist of” the various components and steps. Allnumbers and ranges disclosed above may vary by some amount. Whenever anumerical range with a lower limit and an upper limit is disclosed, anynumber and any included range falling within the range is specificallydisclosed. In particular, every range of values (of the form, “fromabout a to about b,” or, equivalently, “from approximately a to b,” or,equivalently, “from approximately a-b”) disclosed herein is to beunderstood to set forth every number and range encompassed within thebroader range of values. Also, the terms in the claims have their plain,ordinary meaning unless otherwise explicitly and clearly defined by thepatentee. Moreover, the indefinite articles “a” or “an”, as used in theclaims, are defined herein to mean one or more than one of the elementthat it introduces. If there is any conflict in the usages of a word orterm in this specification and one or more patent or other documentsthat may be incorporated herein by reference, the definitions that areconsistent with this specification should be adopted.

What is claimed is:
 1. A method of cementing, comprising: introducing acement composition into a subterranean location, wherein the cementcomposition comprises: a hydraulic cement, a particulate foamedelastomer, and an aqueous fluid; and allowing the cement composition toset in the subterranean location.
 2. The method of claim 1 wherein theparticulate foamed elastomer comprises polyurethane foam.
 3. The methodof claim 1 wherein the particulate foamed elastomer comprises a foamedswellable elastomer.
 4. The method of claim 1 wherein the particulatefoamed elastomer comprises at least one foamed oil-swellable elastomerselected from the group consisting of ethylene propylene diene M-classrubber, polyamide, polypropylene, polyethylene, styrene butadiene,styrene, divinylbenzene, natural rubber, acrylate butadiene rubber,polyacrylate rubber, isoprene rubber, chloroprene rubber, butyl rubber,brominated butyl rubber, chlorinated butyl rubber, chlorinatedpolyethylene, neoprene rubber, styrene butadiene copolymer rubber,sulphonated polyethylene, ethylene acrylate rubber, epichlorohydrinethylene oxide copolymer, ethylene-propylene rubber,ethylene-propylene-diene terpolymer rubber, ethylene vinyl acetatecopolymer, fluorosilicone rubbers, silicone rubbers, poly 2,2,1-bicycloheptene (polynorborneane), alkylstyrene, nitrile rubber, hydrogenatednitrile rubber, fluoro rubbers, perfluoro rubbers,tetrafluorethylene/propylene, any derivative thereof, and anycombination thereof.
 5. The method of claim 1 wherein the particulatefoamed elastomer comprises at least one foamed water-swellable elastomerselected from the group consisting of isobutylene maleic anhydride,starch-polyacrylate acid graft copolymer and salts thereof, polyethyleneoxide polymer, carboxymethyl cellulose type polymers, polyacrylamide,poly(acrylic acid) and salts thereof, poly(acrylic acid-co-acrylamide)and salts thereof, graft-poly(ethylene oxide) of poly(acrylic acid) andsalts thereof, poly(2-hydroxyethyl methacrylate), andpoly(2-hydroxypropyl methacrylate), any derivative thereof, and anycombination thereof.
 6. The method of claim 1 wherein the particulatefoamed elastomer is present in the cement composition in an amount ofabout 0.5% to about 30% by weight of the hydraulic cement.
 7. The methodof claim 1 wherein the particulate foamed elastomer is present in thecement composition in an amount of about 2% to about 10% by weight ofthe hydraulic cement.
 8. The method of claim 1 wherein the particulatefoamed elastomer comprises particulates with a size of about 40 to about1000 microns.
 9. The method of claim 1 wherein the hydraulic cementcomprises at least one hydraulic cement selected from the groupconsisting of a Portland cement, a pozzolana cement, a gypsum cement, ahigh-alumina-content cement, a slag cement, a silica cement, cement kilndust, and combinations thereof.
 10. The method of claim 1 wherein theparticulate foamed elastomer has an open cell structure.
 11. A method ofcementing in a subterranean formation, comprising: introducing a cementcomposition into a space between a pipe string and a subterraneanformation, wherein the cement composition comprises: a hydraulic cement,a particulate foamed elastomer, and an aqueous fluid; and allowing thecement composition to set in the space.
 12. The method of claim 11wherein the particulate foamed elastomer comprises polyurethane foam.13. The method of claim 11 wherein the particulate foamed elastomercomprises a foamed swellable elastomer.
 14. The method of claim 11wherein the particulate foamed elastomer comprises at least one foamedoil-swellable elastomer selected from the group consisting of ethylenepropylene diene M-class rubber, polyamide, polypropylene, polyethylene,styrene butadiene, styrene, divinylbenzene, natural rubber, acrylatebutadiene rubber, polyacrylate rubber, isoprene rubber, chloroprenerubber, butyl rubber, brominated butyl rubber, chlorinated butyl rubber,chlorinated polyethylene, neoprene rubber, styrene butadiene copolymerrubber, sulphonated polyethylene, ethylene acrylate rubber,epichlorohydrin ethylene oxide copolymer, ethylene-propylene rubber,ethylene-propylene-diene terpolymer rubber, ethylene vinyl acetatecopolymer, fluorosilicone rubbers, silicone rubbers, poly 2,2,1-bicycloheptene (polynorborneane), alkylstyrene, nitrile rubber, hydrogenatednitrile rubber, fluoro rubbers, perfluoro rubbers,tetrafluorethylene/propylene, any derivative thereof, and anycombination thereof.
 15. The method of claim 11 wherein the particulatefoamed elastomer comprises at least one foamed water-swellable elastomerselected from the group consisting of isobutylene maleic anhydride,starch-polyacrylate acid graft copolymer and salts thereof, polyethyleneoxide polymer, carboxymethyl cellulose type polymers, polyacrylamide,poly(acrylic acid) and salts thereof, poly(acrylic acid-co-acrylamide)and salts thereof, graft-poly(ethylene oxide) of poly(acrylic acid) andsalts thereof, poly(2-hydroxyethyl methacrylate), andpoly(2-hydroxypropyl methacrylate), any derivative thereof, and anycombination thereof.
 16. The method of claim 11 wherein the particulatefoamed elastomer is present in the cement composition in an amount ofabout 0.5% to about 30% by weight of the hydraulic cement.
 17. Themethod of claim 11 wherein the particulate foamed elastomer is presentin the cement composition in an amount of about 2% to about 10% byweight of the hydraulic cement.
 18. The method of claim 11 wherein theparticulate foamed elastomer comprises particulates with a size of about40 to about 1000 microns.
 19. The method of claim 11 wherein theparticulate foamed elastomer comprises particulates with a size of about60 to about 600 microns.
 20. The method of claim 11 wherein theparticulate foamed elastomer has an open cell structure.